#app {
    height: 100%;
    overflow: hidden;
    background: black;
}

#f {
    /* position: absolute; */
    display: flex;
    flex-direction: row;
    flex-wrap: wrap;
}

#f span {
    background: dimgrey;
    padding: 2px;
    /* 下面这两个属性在Lable里面没有用 */
    /* text-align: center;
    vertical-align: middle; */
}

#f input {
    width: 80px;
    padding: 2px;
    border: 2px;
}

.box {
    width: 50px;
    height: 50px;
    background: rebeccapurple;
}
